\(\frac{45\text{ x16-17}}{45\text{ x}15+28}\)
\(\frac{45 * 16 -17}{\text{45 *15 -28}}\)
\(\frac{45x16-17}{45x15-28}\)\(=\frac{703}{647}\)
Tích tớ nha
Mk chắc chắn đề bài của bn sai, ở mẫu phải là + 28
\(\frac{45x16-17}{45x15+28}=\frac{45x15+45-17}{45x15+28}=\frac{45x15+\left(45-17\right)}{45x15+28}=\frac{45x15+28}{45x15+28}\)
Ủng hộ mk nha ^_-
\(\dfrac{45\text{x}26-17}{28+45\text{x}15}\)
Tính bằng cách thuận tiện.Mong mn giup mik ạ
1.Tính:
45 x 16 - 17
45 x15 + 28
\(\frac{45\times16-17}{45\times15+28}=\frac{45\times15+45-17}{45\times15+28}=\frac{45\times15+28}{45\times15+28}=1\)
45 x 15 - 17/ 45 x 15+28
15.(45-17/45)+28 , 15.2008/45+28 2008/3+28 2092/3
\(\frac{1}{6}+\frac{1}{10}+\frac{1}{15}+\frac{1}{21}+\frac{1}{28}+\frac{1}{36}+\frac{1}{45}=m\text{ấ}y\)
phaỉ giải chi tiết chứ nói như nguyentuantai thì bấm áy tính cũng ra thôi!
\(\frac{1}{6}+\frac{1}{10}+\frac{1}{15}+\frac{1}{21}+\frac{1}{28}+\frac{1}{36}+\frac{1}{45}\)
\(=2\left(\frac{1}{12}+\frac{1}{20}+\frac{1}{30}+\frac{1}{42}+\frac{1}{56}+\frac{1}{72}+\frac{1}{90}\right)\)
\(=2\left(\frac{1}{3\cdot4}+\frac{1}{4\cdot5}+\frac{1}{5\cdot6}+\frac{1}{6\cdot7}+\frac{1}{7\cdot8}+\frac{1}{8\cdot9}+\frac{1}{9\cdot10}\right)\)
\(=2\left(\left[\frac{1}{3}-\frac{1}{4}\right]+\left[\frac{1}{4}-\frac{1}{5}\right]+\left[\frac{1}{5}-\frac{1}{6}\right]+\left[\frac{1}{6}-\frac{1}{7}\right]+\left[\frac{1}{7}-\frac{1}{8}\right]+\left[\frac{1}{8}-\frac{1}{9}\right]+\left[\frac{1}{9}-\frac{1}{10}\right]\right)\)
\(=2\left(\frac{1}{3}-\frac{1}{10}\right)\)
\(=2\cdot\frac{7}{30}\)
\(=\frac{7}{15}\)
Rút gọn biểu thức:
\(I=\frac{\frac{25}{17}-\frac{25}{27}-\frac{25}{37}-\frac{25}{47}}{\frac{45}{17}-\frac{45}{27}-\frac{45}{37}-\frac{45}{47}}\)
\(I=\frac{\frac{25}{17}-\frac{25}{27}-\frac{25}{37}-\frac{25}{47}}{\frac{45}{17}-\frac{45}{27}-\frac{45}{37}-\frac{45}{47}}\)
\(I=\frac{25.\left(\frac{1}{17}-\frac{1}{27}-\frac{1}{37}-\frac{1}{47}\right)}{45.\left(\frac{1}{17}-\frac{1}{27}-\frac{1}{37}-\frac{1}{47}\right)}\)
\(I=\frac{25}{45}=\frac{5}{9}\)
45 x 16 - 17 / 45 x 15 + 28
45x15+45-17=45x15+28=1
45x15+28 45x15+28
\(\frac{\text{0,24 x 450 + 0,8 x 15 x 3 + 3 x 3 x 8 }}{\text{65 -60 ++ 55 - 50 + 45 - 40 +....+ 25- 20 +5}}\)
A) 101 – 100 + 99 – 98 + … + 3 – 2 +1
B) 98 + 87 + 76 + … + 21 – 12 – 23 – 34 - … - 87
C) 168 X 168 – 168 X 56
110
D) 45 X 16 – 17
45 X 15 + 28
E) 864 X 48 – 432 X 96
864 X 48 X 432